Barometer



(No Model.)

m J. G. BUTLER.

BAROMETER.

Patented Mar. 8

UNITED STATES PATENT OFFICE.

JOSEPH C. BUTLER, OF LOUISVILLE, KENTUCKY;

BAROMETER.

SPECIFICATION forming part of Letters Patent No. 359,057, dated March 8, 1887.

Application filed November 12, 1886. Serial No. 218.696. (K0 model.)

To all whom it may concern.-

Be it known that I, JOSEPH O. BUTLER, of Louisville, Jefferson county, in the State of Kentucky, have invented new and useful Improvements in Mercurial Barometers; and I do hereby declare that the following is a full and accurate description of the same, having reference to the accompanying drawings, wherein my invention is represented.

My invention relates to that class of cisternbarometers wherein the tube is in form of asiphon and the cistern constituted by an enlargement of the open upturned end.

It is well known that to fit barometers for transportation it is necessary to force the mercury to fill the vacuumtube to its top and then to lock or securely hold the mercury in that position, because if not entirely filled the tube is liable to be broken by the oscillations of the heavy column of mercury moving in vacuo. Therefore all barometers adapted for transportation are provided with means for raising the mercury in the tube and holding it there. In some a screw is employed to compress the cistern, which is made of collapsible material. In others a stop-cock is employed which is open-way while the instrument is in action and closed-way while fitted for transportation. Both of these methods are too costly for cheap grade instruments.

I propose to accomplish the end desired by constructing the cistern separate from the tube, but connected thereto by a flexible and collapsible sleeve of india-rubber or other suitable material, and providing means whereby said sleeve may be pinched together to confine the mercury and prevent oscillations thereof.

To pinch the sleeve as above stated I prefer to mount the cistern on a table pivoted to the board or frame which supports my barometertube and to pass the sleeve between parts which are caused to close together by tilting said table. Without intending to confine myself to the precise mechanism shown, Iwill, for convenience, describe particularly the structures which I have employed.

Having reference to the accompanying drawings, Figure 1 is an elevation of my barometer. Fig. 2 is a perspective view of the operative parts shown in Fig. 1. Fig. 3 shows the position of the cistern when fitted for transportation. Figs. 4., 5, 6 represent modifications.

A is my barometer-tube, sealed at the upper end, as usual, and with its lower end bent in the form of a siphon. It may be expanded in a bulb, b; but that is not important. I illustrate the invention with the bulb b to show how my improvement may be applied to the ordinary cistern barometer. The tube A is fastened permanently to a suitable back board or frame, G. A second bulb, d, which constitutes the cistern, is connected with the tube A or bulb b by a flexible sleeve, 6, of india-rubber or other suitable material not liable to be affected by contact with liquid mercury. The bulb d is mounted on a table, f, pivoted at h to the tablet G. The edge of tablet f, opposite to the pivot h, is provided with a downwardlyextended prolongation, t, and when said table is turned down on said pivot to a horizontal position said prolongation i makes contact with said sleeve at about its middle of length, collapses it, and pinches the column of mercury at that point, forcing the mercury into the barometer-tube and holding it there; but to securely hold the mercury while the barometer is being moved in transportation it is nec essary to fasten the sleeve on the side opposite to i, and while this may be accomplished by a variety of devices I prefer to make it auto matic. I have practiced various ways, which I show herein, but prefer the pivoted tablet.

Two levers, k m, are pivoted to the back board or frame, G, in such position that the free end of lever m engages with a projecting part, a, of the tablet f as it is turned over on its pivot h, and is thereby pushed outward by said part n. At the same time the other end of lever m engages with one end of lever 7t" and causes the other end of the same to pinch the sleeve 6 against the part i. WVhen turned on its pivot, as above described, the table f and levers m assume such positions that they are mutually locked, and will not move to release the mercury under ordinary circumstances without manual assistance.

The upper end of bulb d is closed with a piece of membrane or other suitable material,

to prevent access of dust to the surface of the mercury, as well as to prevent its accidental escape.

In Fig. 5 is represented a modification, in which the parti moves against a stationary abutment to pinch the sleeve e. This action is shown in Fig. 3. It requires a longer movement of the tablet.

In Fig. 4 a screw-clamp is shown in position to pinch the sides of the sleeve e, and in Fig. 6 a pinching-clamp held by a cord is shown.

If it is desirable to fasten the tablet when turned over, it may be accomplished in a variety of ways. A pin may be inserted through a hole, 19, in both tablet and back board; or, to secure greater reliability, a spring-latch ot'some proper kind or set-screw, 0, may be employed. By these means a cheap barometer, which in all respects is as reliable and accurate as an eX- pensive one, may be adapted for transportation.

Having described my invention, I claim- 1. In a mercurial barometer,a cistern mounted upon a pivoted table and connected with the barometer-tube by a flexible sleeve, 6, ca pable of being forcibly collapsed to divide the mercurial column and lock one part ofthe same in the vacuum-tube, for the purpose set forth. 2. In a mercurial barometer, a cistern composed of two separate bulbs, b and (2, connected'together by a flexible sleeve, 6, said bulb I) being integral with the vacuum-tube, and the other being mounted on a table, pivoted to the tablet G, and thereby made capable of being turned to an angular position as to said vacuum-tube, for the purpose of collapsing said sleeve and dividing the mercurial column to lock one part of the same in the vacuum-tube, as set forth.

3. In a mercurial barometer,.a tube, A, provided with the bulb b, integral therewith, the bulb 01, mounted on the pivoted table f, and the sleeve 6, to connect said bulbs flexibly, whereby said bulbs constitute a cistern capable of being collapsed and pinched at its middle for the purpose of locking the mercurial column in the vacuum-tube.

4. In a mercurial barometer, a tube, A, and a cistern, d, detached therefrom, and a flexible sleeve or connection, e, to connect said tube and cistern, a pivoted table, f, provided with a prolongation, t, at one edge, said cistern being mounted on said table, and the levers k m, adapted to be actuated by said table when it is turned on its pivot to pinch said sleeve and lock the mercury in the vacuum'tube, as 5o set forth.

JOSEPH O. BUTLER.

Witnesses:

WARREN MITCHELL, J osEPH SHORT. 

